. >> reporter: the anc was banned. he became an outlaw, but he refused to back down. arrested in 1962 mandela was charged with sabotage and with attempting to violently overthrow the government. he was convicted and sentenced to life in prison. for decades the struggle for justice in south africa continued with the imprisoned nelson mandela as its symbol. at times he was forced to break rocks in the hot sun for hours at a time. the government offered mandela freedom if he would renounce violence. he refused. >> today marks the 25th year behind bars for nelson mandela. >> reporter: south africa became an international outcast, facing sanctions, boycotts, and growing political pressure. >> nelson mandela should be released to participate in the country's political process. ♪ >> reporter: rock concerts for the cause were broadcast around the world. ♪ hey, mandela >> the release of nelson mandela. >> reporter: in 1989 south africa's hardline president p.w.bota resigned, replaced by f.w. clark who slowly began to dismantle apartheid. the ban on the anc was lifted, and